Divers

20-member group of divers carries the air for 15 hours of diving. 4 members of the expedition sick or wasn't came. How many hours is sufficient air to other divers?

Correct answer:

x =  18.8 h

Step-by-step explanation:

$x={\displaystyle \frac{20\cdot 15}{20-4}}=18.8\text{ h}$

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